As you probably know, heat is one of the enemies of electronics, and heat management is a major design constraint of microelectronics. Now, a German research group has demonstrated using waste heat to get electricity.
No, we’re not really talking about perpetual motion here. What the researchers have observed is that in magnetic …

COMMENTS

Peltier/Seebeck too

Sure you can use these differentials to generate small amounts of power but that is not always helpful.

Anything that extracts energy surely causes resistance to the flow of heat. When you're trying to suck heat out of electronics then that thermal resistance is a Bad Thing since it slows down cooling. To compensate you need a better heat sink.

That means you get a tiny amount of usable energy, but probably need bigger heat sinks. If your system has a fan then you'll need to run the fan more often too - probably using orders of magnitude more power than what you're getting.

" No, we’re not /really/ talking about perpetual motion here. "

perpetual motion requires an efficiency => 1 , you can "break" theoretically Carnot law for Heat Engines without breaking the Thermodynamic Law that disallows you to construct a perpetual motion machine...

my comment points that the shown mechanism is (from a abstract point) a heat engine and, with the given information, no even a lower tier law that is specific for heat engines is broken...

that does not count with the clumsy mismatch of dislike physical parameters, like Voltage and Energy, a type of misinformation only perceptible for people that already know about the subject and easily can confuse other people's understanding.

Bad reporting

The problem is not so much the general public, but the reporters and editors who have no understanding about science. They report on buzz words not science, since they don't have to put any time or effort into writing the article.

It's a thermocouple!

Looks like....

Puzzled by the headline...

I have read this several times and I also fail to see where this breaks the second law of thermodynamics. If there's a temperature difference, and this can be exploited to produce electricity, then there is surely no contradiction. What would be a contradiction with the second law is if useful energy would be extracted from a device at a uniform temperature.

Just calling something "waste heat" is not sufficient - that's just a qualitative term. A thermal power station's waste heat might be a horticulturist's useful source of energy for heating a glasshouse. The clever trick would be to extract any useful work once temperatures have been equalised with the environment. Then somebody can claim a miracle.

"...heated *unevenly*..."

Not breaking the laws of thermodynamics

I don't see a problem here with the laws of thermodynamics.

The first law is basically conservation of energy, and I don't think anyone is claiming that energy is being created or destroyed.

The second law DOES allow for (partial) conversion of heat to work (but you need somewhere cool to dump the rest of the heat) - otherwise the electricity generation system wouldn't work and your car wouldn't start.

Done

Old news

Are these the same guys that came up with Cold Fusion (Electrolisis)? It must be because this is OLD new as well. Thermal Induction eas rather easy to do at home, with some different types of wire, a candle and a volt meter.

Thermodynamics 101 in nine words...

Peltier Cell

So, which manufacturer will be the first to integrate Peltier Cell junctions in their chips, in order to suck heat out of the chip and deposit it in a heat sink to be carried away? I'm referring to actually building the Peltier junctions IN the chips, not bolted onto the top as is currently the practice. After all, most Peltier junctions are semiconductors (Usually Bismuch Telluride, but why not Silicon?), and so are the chips themselves.

Pfft. Amateurs.

So let's install that little thing on all chips. Then feed the resulting current to a* Peltier module. There you go, perpetual cooling! Put your overclocking hats on, kids; ever wanted to know how fast your CPU can be if it runs at 0 Kelvin?

Poor efficiency

The reason thermoelectric generators are not used except is very specialized applications is because even using best metamaterials known, for fundamental thermodynamical reasons, the efficiency is poor and always will be. Typically about 20% of what can be extracted using other (better) Carnot systems. Using magnetic tunnel junctions does not change this.

Breaking of laws??

I see no break in the laws of thermodynamics here. Converting heat to electricity is neat, but hardly a break in thermodynamics. Unless, of course, the conversion is done with perfect efficiency, which doesn't sound like the case here.